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Summary
Topsøe has responded to the demands placed on the sulphuric acid industry to lower SO2 emissions by developing a new sulphuric acid catalyst designated VK-701 LEAP5™. The catalyst is based on Topsøe's novel LEAP5™ technology, which circumvents the transport deficiencies in the molten active phase of existing commercial sulphuric acid catalysts. The VK-701 contains two to three times more active vanadium in the V5+ form compared to other commercial catalysts and, as a result, it offers exceptionally high activity at low temperature in converted strong gases. Kurt Christensen of Haldor Topsøe presented the new catalyst at the Sulphur 2010 Conference in Prague.Abstract
Caesium-promoted vanadium catalysts have been available since the late 1980s and have proved very efficient in reducing SO2 emissions from sulphuric acid plants by providing high activity at low temperatures.
In 1996, Topsøe introduced VK69 designed for operation in the final passes of double-absorption plants1,2. This catalyst offers a very significant activity advantage compared to potassium-promoted catalysts and earlier caesium-promoted catalysts. By installing VK69 in the final pass of existing 3:1 double-absorption plants, the SO2 emission can be cut in half, or the acid production rate can be boosted by 15-20% without increasing SO2 emissions. SO2 emissions below 100 ppm became possible in 3:1 double-absorption plants with VK69.
Summary
BASF has introduced a new high performance Cs-promoted high vanadium-based SO2 oxidation catalyst specially designed for last bed application in sulphuric acid plants.Abstract
In 1913, after a long period of using mostly platinum based catalyst, BASF disclosed groundbreaking patents claiming catalysts for the production of SO3 containing vanadium pentoxide and alkali metal oxides on porous, silica-containing supports, which are still the standard catalysts for industrial production of sulphuric acid today. Under reaction conditions, the alkali metal oxides in the catalyst form a liquid film on the porous silica support wherein the actual active species, a vanadium-containing complex, is dissolved. The properties of this type of catalyst are generally determined by the kind of silica containing support and by the chemical composition of the active compound namely the mixture of alkaline earth sulphates and vanadium pentoxide.
Summary
Ebenezer James of Reliance Industries discusses modifications to the sulphur pastillation and handling facility at Reliance's giant Jamnagar refinery to reduce the formed product's resistance to sulphur dust formation.Abstract
Between 1996 and 2000 Reliance built the world’s largest grass roots refinery at Jamnagar in Gujarat State, on the west coast of India. The complex began life as a 540,000 bbl/d facility, but was expanded over subsequent years to 650,000 bbl/d. From 2006-2008 Reliance then doubled the capacity of the refinery by building a second, almost identical facility next to the original one. Following the commissioning of this second complex, Jamnagar now has the largest refining capacity of any single location in the world.
The new refinery has the built-in flexibility to process numerous grades of crudes varying in terms of acidity and sulphur content. In its first year of operation more than 100 different grades of crude were processed. The complex now exports premium grade fuels to various locations in the world including the US and Europe.
Summary
Amine Experts ran a one day pre-conference Amine Treating Seminar at Sulphur 2010 in Prague. Speakers Egbert van Hoorn and Ben Spooner provided an information packed day discussing amine treating options and best practices, based on their extensive knowledge and experience of amine processes for acid gas treatment. Seminar topics included: principles of gas treating and solvent selection, process control of amine plants, troubleshooting and optimisation, solvent losses and foaming, corrosion abatement, HSAS and solvent degradation.Abstract
The Amine Experts’ Amine Treating Seminar took place on 1 November, 2010 in the run-up to the Sulphur 2010 Conference in Prague. More than 40 delegates attended the seminar from a wide range of backgrounds and countries. The morning started off with Jan Kiebert of Sulphur Experts International welcoming the participants and introducing the speakers of the day. The seminar content , ashotened version of what is normally a five-day seminar, included an introduction to amine treating, a review of the equipment in an amine plant, and discussions on operating conditions, amine plant control, amine losses and foaming, amine plant corrosion, heat stable salts and solvent degradation. By the end of day everyone left the seminar much better informed, having had an intensive and enjoyable day.
Summary
Japan and Korea remain large exporters of sulphuric acid due to their metal smelting industries, while China's insatiable demand for fertilizer makes it a net consumer. But new nickel projects in southeast Asia may affect the balance.Abstract
Like many commodity chemical industries, the global sulphuric acid industry has seen a drift from North America and Europe towards East Asia over the past decade. At the moment, the mature economies of Japan and South Korea produce major export volumes of acid from their metal processing operations, but China has been rapidly expanding both production and consumption of acid, to meet domestic demand for base metals and fertilizers respectively. China remains a major importer of acid, but new regional demand for acid is set to arrive from nickel leaching projects in southeast Asia and Australasia.
Japan
Table 1 shows Japanese production and consumption of sulphuric acid. Consumption of sulphuric acid hit bottom in the first quarter of 2009. Since then there has been a recovery in demand, although not a strong one. Overall acid consumption in Japan is on a long-term declining trend. Production, conversely, is continuing to increase, with a dip in the last year or so caused by the recession. Smelter acid production, especially from copper, is continuing to increase. The overall effect has been to leave an increasingly large surplus available for export.
Summary
Suphur output from refineries continues to increase due to ever-tightening regulations in sulphur in fuels. Sulphur looks at recent and upcoming changes to permitted sulphur levels in fuel.Abstract
Sulphur production by oil refineries has seen a huge increase over the past decade; from around 17 million t/a in 2001 to perhaps as much as 25 million t/a today. That trend is one which is continuing, as countries around the world set ever-tighter limits on permitted sulphur content in fuels. So far it has been fuels for road vehicles – which form the dominant liquid fuel output of all refineries – which have borne the brunt of that, but now regulations are also beginning to tighten on marine ‘bunker’ fuels, and some have suggested that the aviation fuel sector may soon also have to face similar cuts.
Road fuels
Changing regulations in gasoline and diesel road fuels were covered in more detail in our article last year (Sulphur 329, July/August 2010, pp26-29). However, standards continue to change across the world. During the past year, some of the most recent changes have been in India, which adopted a 350ppm limit for sulphur in diesel fuel in April 2010; and China, which has confirmed that the city of Beijing will adopt a Euro-V (10ppm) sulphur limit for diesel fuel in 2012 (most of China is currently on the Euro-III (350ppm) standard).
Summary
This article is a collection of design elements and practical recommendations for seven SRU/TGTU process analysers applications. The emphasis by the authors* is on "best practice", what a good installation looks like, how to avoid past mistakes, process upsets and some relatively new applications.Abstract
Tail gas H2S/SO2
The tail gas H2S/SO2 analyser is the best known of SRU analysers and sometimes for the wrong reasons. The purpose for the analyser is well understood but worthwhile to review.
Combustion air flow within +/- 0.5% is generally achievable resulting in typical losses of 0.2% for a three stage SRU with significant losses of 10% or more due to poor stoichiometry control in the worst cases. The tail gas analyser and feedback control accounts for 2% to 4% of recovery efficiency and contributes more to overall SRU performance than does the third converter (Fig. 1).1
Summary
Catherine Randazzo and Don Messick of The Sulphur Institute argue for sulphur's sustainable credentials.Abstract
Type “sustainability” in your browser. What do you find? Wikipedia will give you multiple screens of text that seek to define and illustrate sustainability. But one site that I find more concise comes from a government source (believe it or not!) – the UK government provides the following definition:
“The goal of sustainable development is to enable all people throughout the world to satisfy their basic needs and enjoy a better quality of life, without compromising the quality of life of future generations.”1
Think for a moment how sustainability might involve sulphur. Surely, as we have moved to an industry where production is dominated by the energy business, we can make the following point: as sulphur is recovered from oil and gas, we are indeed being sustainable with use of the element in well-over 200 applications.
Summary
Problem No. 5 Poorly selected, designed or operated SRU reheaters. This is the fifth in a series of short articles on the subject of "common problems" with Claus sulphur recovery units (SRUs). In this issue, B. Gene Goar discusses "SRU reheaters", based on his wide and varied experience in the design, operation, troubleshooting and remedial problem solving of Claus SRUs.Abstract
Once sulphur is produced in a reaction step of the Claus process, and a sulphur condenser is used to cool the gas down to and below the sulphur dewpoint of the process gas, it is necessary to reheat the process gas sufficiently before it is subjected to the next reaction step. The inlet gas temperature must be increased enough such that the reaction step outlet temperature (typically of a catalytic converter) is at a temperature which is 20-25°F/11-14°C greater than the outlet gas sulphur dewpoint. If this is not accomplished, then sulphur can deposit on and within the catalyst bed and decrease its efficiency dramatically. In other words, the temperature of the process gas out of a catalytic converter should be 20-25°F/11-14°C higher than the sulphur dewpoint of the process gas stream. This is accomplished by reheating the inlet process gas stream sufficiently. The exception to this criteria occurs in the first catalytic converter, where the inlet gas must be reheated sufficiently high to accomplish proper COS and CS2 hydrolysis in the catalyst bed (normally this requires a bed outlet gas temperature of 600-620°F/316-327°C).
Summary
Sulphur's annual survey of recent, current and future sulphur recovery unit construction projects maps the developing shape of brimstone production from fuel and gas processing plants worldwide.Abstract